The disclosure of U.S. Provisional Application No. 61/491,529, filed May 31, 2011, is hereby incorporated herein in its entirety by reference.
Agricultural harvesting machines, such as combines, comprise a variety of apparatus and systems for receiving and processing crops. In particular, a combine will include a header operable for severing crops and other plant material from root structure and conveying the severed crop and plant material to a feed mechanism of the combine. The feed mechanism will typically include an enclosed feeder housing containing a feed conveyor, which feed conveyor will typically include parallel chains connected by slats, which chains encircle sprockets which are driven by a feeder drive to move the chains and slats upwardly and rearwardly along a floor of the housing, for inducting and conveying the crop and plant material, as well as debris that may be contained therein, into an inlet region of a threshing system of the combine. The threshing system, in turn, will typically include at least one rotor rotatable within a cavity or space defined at least partially by a concave structure having an array or arrays of openings therein sized for passage of grain therethrough. The rotor will include elements for inducting the crop and other material into the cavity and conveying the material through a crop separation clearance between the outer region of the rotor and the inner region of the concave, for separating grain and other small elements of the crop material from larger elements thereof, typically including leaves, stalks, cobs, husks and the like, depending on the crop being harvested. The separated grain is then expected to pass through the openings of the concave for further processing.
From time to time during operation of an agricultural combine, a slug, that is, an incorrectly processed and/or compacted mass of crop material and/or weeds, particularly stringy or viny weeds, debris, or other material, may be inducted into the feed mechanism and/or the threshing mechanism and become lodged or packed or jammed, to possibly block or interrupt throughput of crop material through the combine, and/or damage components of the feed and/or threshing mechanism, thus necessitating removal of the blockage or slug. Thus, when the combine encounters a slug of crop which plugs the draper sickle knife, feed draper, feed auger, feeder house, or threshing rotor, the operator must stop the normal forward feeding of crop and momentarily reverse the feeding mechanisms in an attempt to break up the slug of crop and eventually continue harvesting.
Once a slug has developed in the crop processing mechanism which refers to the feed mechanism and the threshing mechanism of the combine, a number of different actions depending on, the combine status, the type, severity and location of the slug, may be necessary to effect removal of the slug. These actions in response to encountering a slug or blockage of crop material may be performed by the operator, selected by the operator from a number of predetermined deslugging routines, or automatically run as a function of sensed parameters representative of the type and location of the slug or blockage. One such system and method is described in Bundy et al., U.S. Pat. No. 7,452,267 issued Nov. 18, 2008 to CNH America LLC which is herein incorporated by reference.
Actions in response to a blockage or slug in the crop processing mechanism may only entail backing the slug or blockage away from the mechanism at which it became lodged, sufficiently so as to break it up or better process or compact it for passage through the feed and/or threshing mechanism. A slug or blockage that cannot be sufficiently broken up to pass through the mechanism may be carried off the front of the header by reversing one or both mechanisms to discharge the slug or blockage onto the feed draper and reversing the feed draper to carry the slug or blockage from the front of the header.
For a slug or blockage in the threshing mechanism, it may be sufficient to repeatedly jog the rotor through small angular movements, until the resulting low impulsive loads break down the slug and free it. In a more extreme example, it may be necessary to rock the rotor more violently back and forth in an agitating motion, at different amplitudes and different frequencies, occasionally with an asymmetric motion and relatively large impulsive loads, for extended periods of time, to incrementally dislodge or work the slug free. In an even more extreme example, manual intervention may be required, to open up the feed mechanism and/or the threshing mechanism, and manually clear the slug piece by piece.
Once the slug or blockage has been cleared, normal crop processing resumes and the draper header again conveys crop material to the feed mechanism. The distribution of the crop material on the feed and side drapers at this point depends on their operation during the deslugging operation. For example, if the feed and side drapers continue in their normal operating direction during the deslugging process, the side belts continue to add more crop material to the center belt which is counterproductive to the unplugging process. In other words, crop material distributed along the side drapers when the combine stopped harvesting is fed onto the feed draper and toward the inlet of the feeder housing. When normal operation resumes, all of the crop material that was distributed along the draper header simultaneously enters the feed mechanism, potentially leading to another blockage. As another example, if reverse operation of the feed and side drapers is disabled during the deslugging operation, the operator will not have the option of discharging a slug from the front of the header. Another option is to reverse both the feed and the side drapers during the deslugging operation. Reference in this regard, Enns et al., U.S. Pat. No. 7,497,069 issued on Mar. 3, 2009 to MacDon Industries Ltd., which describes a hydraulic circuit that reverses both the feed and side drapers during reverse operation of the feed and/or threshing mechanism. Reversing the feed draper, when not clearing a slug or blockage from the front of the header, results in unnecessary loss of the crop material on the feed draper when harvesting stopped. In addition, reversing the side drapers results in accumulation of the crop material on the side drapers at the outer ends thereof that will later be fed into the feed mechanism potentially leading to another blockage.
Accordingly, what is sought is a system and method for operating a draper header during and subsequent to a slug clean out operation, which provides one or more of the capabilities and overcomes at least one of the problems, shortcomings or disadvantages as set forth above.